• 한국통신학회논문지
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• 제27권1A호
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• pp.42-50
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• 2002

본 논문에서는 소수 p에 대해 이상적인 자기상관특성을 갖는 p진 d-동차시퀀스를 발생시키기 위한 생성방법을 제안하고 Helleseth와 Kumar, Martinsen이 찾아낸 3진 d-동차시퀀스를 이용한 이상적인 자기상관특성을 갖는 3진 d-동차시퀀스를 소개하였다. p진 확장시퀀스(기하시퀀스의 특별한 경우)의 방생 방법과 p진 d-동차시퀀스의 발생방법을 조합하면 이진과 p진 확장 시퀀스, d-동차시퀀스 모두를 포함하는 매우 일반적인 행태의 이상적인 자기상관 특성을 갖는 p진 통합(확장 d-동차)시퀀스의 발생 방법을 제안하였다. 또한, Helleseth와 Kumar, Martinsen이 발견한 이상적인 자기상관특성을 갖는 3진 시퀀스로부터, 이상적인 자기상관특성을 갖는 3진 통합시퀀스를 생성하였다.

• 한국정보통신학회논문지
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• 제15권10호
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• pp.2181-2187
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• 2011

본 논문에서는 GMW 수열과 No 수열에 의해서 생성된 이진 수열들의 집합을 소개하고 분석한다. 집합안의 각 수열들은 주기 $N=2^n-1$이고 n=2m 이며 $2^m$개의 수열들이 있다. 합성된 수열의 자기상관계수와 상호상관계수 그리고 선형스팬을 구한다.

• Journal of Electrical Engineering and information Science
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• 제2권6호
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• pp.217-222
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• 1997

Recently, No et al. presented a new construction of binary sequences with ideal autocorrelation property. In this paper, we applied this method into some of the well-known binary sequences with ideal autocorrelation, and the results are described in detail. First, the GMW sequences are shown to be a natural extension of m-sequences with respect to this method. Second, new binary sequences with ideal autocorrelation property are explicitly constructed from Legendre sequences, Hall's sextic residue sequences, and other known sequences of miscellaneous type.

• International Journal of Contents
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• 제3권2호
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• pp.18-24
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• 2007

Biological sequences such as DNA and amino acid sequences typically contain a large number of items. They have contiguous sequences that ordinarily consist of more than hundreds of frequent items. In biological sequences analysis(BSA), a frequent contiguous sequence search is one of the most important operations. Many studies have been done for mining sequential patterns efficiently. Most of the existing methods for mining sequential patterns are based on the Apriori algorithm. In particular, the prefixSpan algorithm is one of the most efficient sequential pattern mining schemes based on the Apriori algorithm. However, since the algorithm expands the sequential patterns from frequent patterns with length-1, it is not suitable for biological datasets with long frequent contiguous sequences. In recent years, the MacosVSpan algorithm was proposed based on the idea of the prefixSpan algorithm to significantly reduce its recursive process. However, the algorithm is still inefficient for mining frequent contiguous sequences from long biological data sequences. In this paper, we propose an efficient method to mine maximal frequent contiguous sequences in large biological data sequences by constructing the spanning tree with a fixed length. To verify the superiority of the proposed method, we perform experiments in various environments. The experiments show that the proposed method is much more efficient than MacosVSpan in terms of retrieval performance.

• Genomics & Informatics
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• 제5권2호
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• pp.68-76
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• 2007

Due to the increasing interest in SNPs and mutational hot spots for disease traits, it is becoming more important to define and understand the relationship between SNPs and their flanking sequences. To study the effects of flanking sequences on SNPs, statistical approaches are necessary to assess bias in SNP data. In this study we mainly applied Markov chains for SNP sequences, particularly those located in intronic regions, and for analysis of in-del data. All of the pertaining sequences showed a significant tendency to generate particular SNP types. Most sequences flanking SNPs had lower complexities than average sequences, and some of them were associated with microsatellites. Moreover, many Alu repeats were found in the flanking sequences. We observed an elevated frequency of single-base-pair repeat-like sequences, mirror repeats, and palindromes in the SNP flanking sequence data. Alu repeats are hypothesized to be associated with C-to-T transition mutations or A-to-I RNA editing. In particular, the in-del data revealed an association between particular changes such as palindromes or mirror repeats. Results indicate that the mechanism of induction of in-del transitions is probably very different from that which is responsible for other SNPs. From a statistical perspective, frequent DNA lesions in some regions probably have effects on the occurrence of SNPs.

• Investigative Magnetic Resonance Imaging
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• 제4권1호
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• pp.20-26
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• 2000

Gradient moment nulling techniques require the introduction of an additional gradient on each axis for each order of motion correction to be applied. The additional gradients introduce new constraints on the sequence design and increase the demands on the gradient system. The purpose of this paper is to demonstrate techniques for optimization of gradient echo gradient moment nulling sequences within the constraints of the gradient hardware. Flow compensated pulse sequences were designed and implemented on a clinical magnetic resonance imaging system. The design of the gradient moment nulling sequences requires the solution of a linear system of equations. A Mathematica package was developed that interactively solves the gradient moment nulling problem. The package allows the physicist to specify the desired order of motion compensation and the duration of the gradients in the sequence with different gradient envelopes. The gradient echo sequences with first, second, and third order motion compensation were implemented with minimum echo time. The sequences were optimized to take full advantage of the capabilities of the gradient hardware. The sequences were used to generate images of phantoms and human brains. The optimized sequences were found to have better motion compensation than comparable standard sequences.

• 한국정보과학회논문지:시스템및이론
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• 제36권4호
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• pp.231-238
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• 2009

DNA 서열은 각 종을 나타내는 근본적인 정보이며, 다른 종 간의 DNA 서열 비교는 중요한 작업이다. DNA 서열은 길이가 매우 길며 또 종의 종류도 다양하기 때문에, DNA 서열 비교에서는 빠른 매칭 뿐만 아니라 효율적인 저장도 중요한 요소이다. 즉, 인코딩 된 DNA 서열에 적합한 빠른 문자열 매칭 방법이 필요하다. 본 논문에서는 매칭 시 디코딩이 필요하지 않은 인코딩 된 DNA 서열을 위한 빠른 매칭 알고리즘을 제시한다. 제시하는 알고리즘은 네 문자 한 바이트 인코딩을 이용하며 서픽스 기법과 다중 패턴 매칭 기법을 접목하고 있다. 실험 결과로는 본 논문에서 제시하는 방법이 AGREP보다 약 다섯배 빠름을 보이는데, 이는 알려진 알고리즘들 중에서 가장 빠른 결과이다.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.278-281
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• 2012

Comparative sequence analyses were conducted on complete mtDNA sequences from four small mammal species in Korea and revealed the presence of 30 well conserved sequences in various regions of the complete mtDNA sequences. The conserved sequences were found in 9 regions in protein coding genes, 10 regions in tRNA genes, 10 in rRNA genes, one region in replication origin and 2 regions in D loop. They could be used to design primers for amplifying complete mtDNA sequences of small mammals.

• 전자공학회논문지B
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• 제30B권12호
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• pp.40-50
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• 1993

This paper presents a new method for generating assembly sequences. The method acquires constraints on sequencing the assembly tasks without redundancy. Then it generates the assembly sequences without seatching undesirable tasks by recursively searching all assembly tasks which do not violate the assembly constraints. Since the method does not search undesirable tasks, it can generate assembly sequences for complex products. Current available methods may not generate assembly sequences for the complex product since their search-space increases explosively as the number of parts rises.

• Journal of the Korean Statistical Society
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• 제24권1호
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• pp.249-256
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• 1995

In this note we prove an invariance principle for strictly stationary linear positive quadrant dependent sequences, satifying some assumption on the covariance structure, $0 < \sum Cov(X_1,X_j) < \infty$. This result is an extension of Burton, Dabrowski and Dehlings' invariance principle for weakly associated sequences to LPQD sequences as well as an improvement of Newman's central limit theorem for LPQD sequences.